Yes I know. After the Lace, Vibram came out with the R419 and 420. The 419 became the unLace, but the 420 was deemed too overstable to be the O-Lace mold they were hoping for.

But they did release the R420 as the 420, and then the Solace after it got some negative press.

But my point is, I know they went back to the drawing board on making something in between the Lace and the Solace, and ended up coming out with at least one short run of O-Lace's that were deemed to be too under stable and therefore too similar to the Lace, before they retooled and came out with the modern O-Lace.

I'd just like to know if there's a way to spot the "bad" run of O-Laces, because I think there are some in circulation and I don't want to pick one up by accident.

I have no idea if they changed this or not, but the 'flight chart' that is stamped on the back of my O-Lace is for a LHBH (or RHFH) throw. I recall reading somewhere (or maybe just imagined it) that this was just a simple mistake of placing the mold in backward and that it would be corrected. If so, and the stamp now shows RHBH for the flight, you can likely find the earlier run O-Laces by way of that LHBH stamp.